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Chen et al. Soft Sci. 2026, 6, 9 Page 3 of 36

spaces . The first advantage of magnetic manipulation is remote and non-contact manipulation with high
[46]
spatial precision, allowing for complex deformation and locomotion without bulky mechanical
connections [47,48] . This is particularly attractive in confined environments such as the human body, where
tethered actuation is impractical. Second, magnetic manipulation is energy-efficient and rapid, since the
interaction between magnetic fields and inside current or embedded magnetic components can provide
instantaneous force transmission . Third, magnetic manipulation allows for scalable and programmable
[49]
control through tailored field gradients or dynamic field modulation, enabling sophisticated functionalities
like reversible shape-morphing, droplet splitting/merging, and collective behaviors in miniature LM soft
robots . Additionally, this method exhibits excellent biocompatibility, since moderate magnetic fields are
[50]
non-ionizing and pose minimal risk to biological tissues, making it suitable for biomedical applications such
as targeted drug delivery and minimally invasive surgery [47,48] . The unique advantages of magnetic
manipulation position it as a promising strategy for LM soft robots, a prospect that has attracted growing
attention and some recent reviews [41-43] . While these earlier reviews primarily categorize magnetic
manipulation of LMs by application scenarios (e.g., flexible electronics and soft robotics), our review adopts
a fundamentally different perspective. Here, we propose a type-oriented classification framework that
systematically links distinct forms of LMs (i.e., droplet, slurry, particle, and composite) with their
corresponding characteristics, functionality, and applications [Figure 1]. This approach offers a more
actionable basis for selecting or engineering LM materials for targeted magnetic manipulation. In addition,
distinct from earlier overviews prioritizing direct magnet-particle interactions, our review highlights the
pivotal role of Lorentz force mechanisms in magnetically manipulated LM systems. These changes expand
the scope of the discussion on mechanisms of magnetic manipulation and practical applications.

In this review, we systematically discuss the magnetic manipulation of LM for soft robots, encompassing
material preparation, manipulation mechanisms, and practical applications [Figure 1]. First, we summarize
methods for preparation of magnetic liquid metal (MLMs), integration of MLMs with other soft materials,
and patterning of LMs. Then, different mechanisms for magnetic manipulation of LMs, including magnet
manipulation and Lorentz-force manipulation, are presented and compared. In addition, multi-field
manipulation of LMs, by combining other physical fields (e.g., electric, thermal, and acoustic fields) with
magnetic fields, is also highlighted. With distinct constitutions and morphological characteristics,
magnetically manipulated LM soft robots are categorized into four types: droplet, slurry, particle, and
composite. Their diverse applications span reconfigurable electronics, biomedical engineering, and
environmental remediation. Finally, we address current challenges and opportunities in material
optimization, precise manipulation, and future applications. This overview summarizes the current
landscape of magnetically manipulated LM soft robots and offers guidance for their prospective development
in medical, electronic, and industrial domains.

PREPARATION OF MAGNETICALLY RESPONSIVE LMs
LMs responsive to external magnetic fields can be categorized into two distinct groups based on the origin of
their magnetic properties. The intrinsic materials exploit Lorentz forces on mobile electrons under external
magnetic fields, enabling magnetic manipulation without compositional modification. Composite MLMs, by
contrast, incorporate magnetic particles such as Fe, Ni, and Fe O 4 [41-43] . In this case, extrinsic magnetic
3
responsiveness arises from direct coupling between embedded magnetic particles and external magnetic
fields. Owing to the strong magnetic responsiveness and superior design versatility, particle-integrated
MLMs have attracted increasing attention and currently represent the primary focus of research in this
field [41-43] .

In this section, preparation of MLMs is categorized into two methods: mechanical and chemical methods. A
third category encompasses other approaches, including those used for the integration of MLMs with other

materials and for patterning of LMs.